So I got a PowerBook G4. Yay! Only problem is, Mac OS X 10.5.8 is just borderline useful in 2016, especially on a PowerPC machine with 512MB RAM. That, and I grew frustrated with the way how Mac OS X is designed. So, I decided to install Linux on it. Here's how things went down:
 

• Downloaded Ubuntu MATE 15.10 PowerPC ISO
• Wrote it to an 8GB flash drive using LiLi
• Tried booting to it, it wouldn't boot
• Tried using the Mini ISO instead
• Mini ISO was missing a lot of things
• When I finally got it working, it was missing a lot of kernel modules (among other things) and was incredibly slow, almost slower than Mac OS X was; it was also extremely prone to breaking
• Finally figure out what I was doing wrong, used dd to write the ISO to the flash drive instead of LiLi and it booted
• Installed Ubuntu graphically, after working around a bug I encountered early on in my adventure that causes Ubuntu to crash if I don't type "radeon.agpmode=-1" into the yaboot prompt when booting or yaboot.conf file
• Using nano in a tty, I added "radeon.agpmode=-1" to yaboot.conf, updated the boot partition and rebooted to keep it from crashing
• Couldn't get wireless working, still used Ethernet for internetting
• Got sound working by editing the config files and alsamixer in a terminal
• Still couldn't get wireless working, put in an 802.11g PC Card into the PCMCIA slot instead

And now I have a more useful PowerBook G4. Runs much better than OS X did, too, and it'll run even better when I upgrade it to 2GB RAM. Maybe an SSD too... but getting to this point took so friggin' long and I'm glad it's over.